Serious Saitama
by Gaming Ikari
Summary: Saitama's dream of an all-powerful subterranean invasion isn't a dream, it's fact. He wakes up to subterraneans grabbing his face and throwing him through his apartment, and everything that follows as the Hero Association tries to save the fragments of the human race.
1. Chapter 1

Serious Saitama

Chapter 1: 70% of the Planet

oOo

It was total pandemonium. It was chaos. This was the crisis the Hero Association had been put together to fight. This was the crisis which only the Hero Association was equipped to deal with.

It was the highest threat level: **Kami.**

Reports from all over were indicating that the invading force of underground monsters were strong. Too strong. Anyone but an S-Class Hero could only stall them, not fight them head on and hope to defeat them. Entire cities were being annihilated, even as the S-Class Heroes were dispatched to the cities they could protect, dooming other cities too far to be reached before they were effectively crushed by the subterranean uprising. A-Class and B-Class Heroes fought desperate delaying actions, while C-Class Heroes performed rescues and otherwise helped with evacuations.

That didn't trouble the bearded man who was directing all of the operations, however. What bothered him was the concentration of the enemy threat on Z-City, and how it was being halted. Every S-Class Hero except for Blast was accounted for, halting threats in other cities. Likewise every A and B-Class Hero was accounted for, fighting desperate stalling actions as they waited for an S-Class to come.

However... Shortly after the attack emerged, Z-City had been hit with 90% of the enemy forces, and _something_ was stopping those forces cold. _Something_ was drawing more and more enemy reinforcements to just one spot, and whatever it was... It was chewing through those reinforcements far faster than even Tatsumaki was handling her own foes when she reached them.

The coordinator decided to trust in whatever was halting the enemy there, directing Heroes as he worked to save as much of humanity as possible.

"Atomic Samurai. No more enemies," a voice drifted in. The man glanced desperately at the scanners, frowning.

"Please, Stinger and Lightning Max's group is struggling with some of the enemy in K-City. We'll send air support to get you there!"

"No need," the voice replied, grunting once before the transmission cut off.

More enemy signatures disappeared from the scanners.

"Got anything better?" Tatsumaki's voice demanded, and the administrator could hear the frown she no doubt wore.

"Fubuki's group is struggling with enemies in G-City," he noted, studying the map.

He didn't get a reply, but noted that Tatsumaki's transponder was moving with a speed towards G City which bordered on the ridiculous.

"These things hit hard," Silver Fang's voice complained, though it was easy to see he'd killed his foes. "Where to next?"

"L-City needs back up. Mumen Rider has lead some of the enemy away from an evacuation group, but I don't even know how he's lasted as long as he has," the coordinator responded, frowning. He tapped a few more buttons. "I'm sending you the coordinates now. Please try to get to him in time."

"On the way," Bang's voice replied, the transmission ceasing.

Slowly, steadily... The Hero Association was driving the fringes of the invasion back. It was straining the very limits of their resources, but every attack but the one on Z-City was beginning to die off, be driven back under the ground.

Which begged the question: What the hell was going on in Z-City that was more important to the enemy than any of the S-Class Heroes they'd fielded? Even Metal Knight, unconcerned with civilian casualties at this late stage, was not dealing as much damage as whatever was fighting in Z-City.

"Metal Bat reporting in. K-City's wrapped up. What do you want me to do now?" The punk's voice came over the transmission.

They needed more information.

"Metal Bat, something is fighting the majority of the enemy forces. The Hero Association has only been fighting the leftovers. Head to Z-City and find out what the hell is taking the brunt of this attack and give us a report," the coordinator responded, frowning at the order. He wasn't sure if it was fair to ask it of Metal Bat, but they needed the information. Badly.

"We've been hit this hard and we're just dealing with the extras?" Metal Bat's voice was equally frightened and intrigued. "I've got to see whatever the hell group is strong enough to fight ten times as many of these things as we've all been fighting until now!"

"Tatsumaki here," the esper's voice carried over the comms as well. "Unless you have something better for me to do, I'll head to Z-City as well. G-City's situation is handled."

The administrator noted that the rest of the S-Class heroes more or less had everything under control for now and nodded, "Meet up with Metal Bat, Tatsumaki. I'll send more as soon as I can."

Z-City would be where this war was won or lost, and he'd throw as many S-Class Heroes at Z-City as he had to spare, as soon as he had them.

oOo

Metal Bat nearly dropped the weapon which gave him his name as he stared across the battlefield which had once been Z-City, perched on an eight-floor building which gave him a good view of the battle in progress.

He'd fought nearly thirty of the subterraneans in K-City, and had he not been able to draw them into one on one fights while the A-Class Heroes drew off the rest, he would have been overwhelmed in an instant. They were damned near as strong as he was, but not quite. He held just enough of an edge to beat them head on.

Just.

Then he'd fought one of the large ones. It had been stronger, faster, and tougher than he was. He'd taken a few blows he would have preferred not to take in beating down that monster, blows which slowed him down even now, in the long run.

The strength boost he got from a beatdown worked for a few minutes, but Metal Bat wasn't immortal: Those muscle tears and bruises caught up with him faster than he would have wanted.

As far as the eye could see, the bodies of hundreds of the large types, and thousands of the smaller surface invaders littered the landscape of Z-City, so dense that the subterranean reinforcements needed to burrow through their dead to reach the surface.

What drew Metal Bat's attention, however, was the man at the center of it all. Bald and nondescript, dressed in nothing but some slightly tattered blue and white pajama bottoms... Even as the S-Class Hero watched, the man was killing every enemy who launched themselves at him with a single strike.

Three of the smaller subterraneans timed their jump to strike at once, odds the punk wouldn't have liked to face. The nobody in the pajama pants blocked all three strikes, grinned, and then swept their legs out from underneath them, gathering all three on his fist as he spun before driving them into the ground, creating an obscene wave of corpses from the point he'd struck, shaking the steam off of his fist before meeting the charge of two of the large ones.

The closer subterranean swung a punch at the unnamed hero, who spun around the haymaker to punch the large subterranean in the throat, blowing its head clean off before planting his hands on the dead creature's shoulders, launching himself over the other large subterranean's hands as the other creature crushed what remained of the dying one's torso.

One punch ruptured the creature's chest, blowing the large limbs away as every part of the large subterranean's torso was turned from solid to liquid in a single strike.

"HQ, come in," Metal Bat whispered, awed.

"Metal Bat, we hear you. What can you see?" The Hero Association administrator demanded.

"It's one guy. He's crushing them like Snek crushing new B-Class Heroes. Even the big ones. He's annihilating them," the punk grunted, frowning. How the hell was someone that strong!? "The enemy is digging through a battlefield littered with corpses just to get to this guy. Just in the last minute, he's taken out way more than I fought in K-City."

"Do you recognize him?" The administrator demanded.

"Not at all," the punk replied, watching as the unnamed hero crushed another dozen of the subterraneans with the same ridiculous ease. "He barely looks winded, and he's beating them down with just one punch. Are we sure this guy isn't Blast?"

"He's not. Whoever that is, he's not S-Class One, Blast," the administrator confirmed.

"He might not be Blast, but if he were in the Hero Association, he'd be S-Class One," Metal Bat disagreed, watching the man build a pile of bodies as he fought. Not all of the subterraneans were blasted into paste when hit, but not a single one of them stirred after taking a single hit. He glanced up to see Tatsumaki arriving on the scene, the green-haired esper's mouth forming a silent O at the destruction in front of her. Metal Bat smirked. "Did someone get upstaged, Tatsumaki-chan?"

The woman's temper must have been on thin ice, but thankfully her shock at the scene in front of her prevented her from going full tsun-tsun on him, as Metal Bat felt his personal gravity lift, but not subsequently slam him into the tower for his impudence.

"Hmph! They were just too scared to fight me!" Tatsumaki finally declared, releasing her fellow S-Class. "They came after this guy instead of having to fight me!"

Even Metal Bat recognized the lie. He knew she recognized it, as well.

Whoever this man in his pajamas was, he was fighting on a level as far above S-Class as an S-Class was above a B-Class. Opponents that he and Tatsumaki would take seriously were being treated trivially by the bald man as he struck more and more down with a single strike.

"Why do I get the impression I'd just be in the way if I went down there?" Metal Bat grumbled.

"You would," Metal Knight's voice chimed in, the heavy artillery platform he'd been favoring lately drifting to rest on the building. The faceless head of the machine didn't acknowledge the other two S-Ranks, instead focusing on the battle in front of them. "I was debating concentrating my fire on the battlefront. Right now all of these subterraneans are focused on that bald man, and I could take out plenty of them with one strike... But then they'd scatter and focus on us instead. I won't fire until he falls. We'll only get once chance at this."

"Waiting to take the credit until the end?" Silver Fang asked, joining the Heroes on the rooftop, landing lightly next to Metal Bat.

"How long could you survive down there, Silver Fang?" Metal Knight demanded in reply. Bang studied the fight, watching the endless stream of the subterraneans as they closed on the bald killing machine at the center of Z-City.

"Two minutes. Maybe three. I wouldn't be killing them at nearly the rate he is, though," the older Hero finally admitted, frowning down at the sight in front of him.

"I could just summon a storm of rubble and annihilate them all," Tatsumaki sniffed, frowning at the enemies.

"Same problem as Metal Knight," Metal Bat countered, frowning at the melee happening in front of them. "You might take out the baldy, and then we'd have to deal with all of the ones swarming him. That's not a fight I think I can win, even if part of me wants to try."

They all silently watched the man continue to fight, effortlessly blowing through the horde with raw power, never engaging his enemies, just blowing past them. Before long, Atomic Samurai had arrived on the scene, hand resting easily on the katana at his side. The Iaijutsu master took only a few seconds of watching the fight before his jaw dropped.

"Bang, you see it, right?" Atomic Samurai demanded, frowning at the fight in front of him.

"What's there to see?" Metal Bat interjected, frowning and tapping his bat idly against his free hand. "This bald bastard is beating the subterraneans down like nobody's business. What's so surprising about it? That bastard is strong."

"He's utterly unskilled," Silver Fang stated, nodding once in agreement with Atomic Samurai. At the confused glance of every other S-Class Hero present, he continued. "Atomic Samurai and I would be A-Class Heroes, if it weren't for our skill at martial arts. In a direct, strength against strength situation we couldn't hope to stand up to the likes of even Metal Bat, let alone Tatsumaki-san: We close our gap with them through pure skill, not overwhelming power."

"So this guy..." Metal Bat prompted, earning a nod from Atomic Samurai.

"He's raw power. Just enough skill to control it, but he's as green as it comes when it comes to technique," the Iaijutsu master confirmed. "If it were equal power, any S-Class Hero outside of Tatsumaki-san would probably know enough to thrash this guy with ease, but..."

"But?" Tatsumaki demanded, crossing her arms and frowning at the one-man war the baldy was winning in front of her.

"Technique doesn't matter when your foe is so strong that technique won't evade his blows," Bang finished, gazing down at the fight with undisguised interest. "That man's blows are so strong, so fast that you can't deflect or counter them. The only way to avoid death is to dodge completely: Even a glancing blow would kill you. And he moves so fast that you'd have to be more skilled than I am to avoid them completely."

The subterraneans burrowing through the ground slowed their attacks, then finally stopped, one last one dying and leaving the unknown powerhouse with no more foes to fight. A light rain began to pour from the sky, the bald man in his tattered pajama pants blowing plumes of hot steam into the suddenly cool air as he finally rested, his work finally done.

Slowly the man tilted his head up to the rain, having regained his breath, apparently relishing the cool droplets now falling down on him if the grin on his face was any indication. The S-Rank Heroes gathered noticed then, that the only wound evident on his body was a small cut above his left eyebrow.

Silver Fang had only taken a single step towards the battlefield when one of the mountains of corpses was shattered, a new subterranean emerging from the shower of corpses littering the battlefield. Unlike the rest, this subterranean was larger than even the type the Hero Association had been calling Large. Also unlike the rest, it had four arms rather than two, and in each fist it clenched a blade which seemed to be made of pure green energy, the rain showering the region hissing as it met them.

Upon seeing the latest threat, the smile on the bald man's face was like a child seeing the sunlight for the first time. It was a smile that was pure in a way Bang couldn't describe, really. It held an echo of his own joy the first time he'd been challenged, but was somehow magnified a million times.

The smile was the smile of a man who thought he'd finally found a good fight, the smile of a man who'd trained himself to the utter edge of what was possible and wanted to fight another being who'd pushed themselves to the same limit. The smile of a man who'd finally found a being who could, until their fight was ended, be treated as his equal.

Until they found out who was the stronger.

Ignoring the corpses underneath his feet, the bald man began running with reckless abandon towards the last of the subterraneans, the last of the foes which had emerged to plague the world.

Four blades of pure energy so intense Metal Bat could taste them closed on the bald man, and he just grinned, punched, and the blades shattered, the bald man in his pajamas torquing his body to deliver a follow-up punch to the chest of the subterranean which blasted the giant being back across the shattered cityscape, pushing itself up from where it was propped up by an abandoned apartment building.

The bald man was already within punching distance when the creature raised it's head to regain it's bearing.

One punch blasted the subterranean's head clean off it's shoulders, leaving the bald man to stand briefly on the creature's chest for a moment, staring at his fist.

"My apartment!" The first words the bald superhero had said in the battle, and then the man disappeared, moving too fast for Metal Bat to comprehend. A quick glance at his fellow heroes and their astonishment at what had happened confirmed that none of them had followed what he'd done.

"...The world is clearly a larger place than we think," Bang noted, frowning a bit. "How the hell did we miss someone with that much strength?"

oOo

Author's Notes:

ONE PUUUUUUUUUUUUUUUUUUNCH!

Sorry.

Plot bunny. Given the nature of the story, probably ten chapters at best. Basically, Saitama's dream fight happens, 70% of humanity is destroyed, and the Hero Association has to deal.

Basically, Saitama is basically known for how strong he is, but not known identity-wise.

Dis gonna be fun.

-Gaming Ikari


	2. Chapter 2

anfSerious Saitama

Chapter 2: His Student

oOo

Genos had been unprepared for the monster woman.

That much was plain to him the moment he actually engaged her, given the speed with which she ruined him. The mosquito monster girl had him in a position where his best bet was to kill himself by overloading his reactor, taking her with him, when **HE** appeared.

 **HE** basically walked out of nowhere in the middle of the decimated remains of Z City and slapped the creature into a fine paste, after showing up and getting his clothing roasted off him in the middle of a fight the cyborg could barely win, let alone worry about collateral damage. **HE** had brushed off the block-wide inferno without even worrying about the clothing which had burned off of **HIM.**

Genos was pretty sure **HE** expressed him mutter some discontent about mosquitos, but given that this civilian-looking person had just casually ended a creature Genos had been unable to fight, Genos wasn't really focusing too much. The data was recorded, but not registered as important next to the way **HE** 'd just...

 **HE** 'd just slapped the mosquito girl.

 **HE** 'd swatted her like a mosquito, and the only thing that remained of her after the open-handed slap was the red blood which **HE** 'd splattered across the building.

Then **HE** 'd just moved to walk away, like **HE** 'd swatted a regular insect, oblivious to the fact she'd been able to push the cyborg to the brink of death, pushed Genos to the point where even the Doctor's latest upgrades had left him helpless to stop the events in front of him.

Genos knew he wasn't weak, but this man's strength... He needed to know the secrets to it. The creature which had made Genos go to the Doctor Stench to be turned into what he was, that monster from the young man's nightmares was strong enough that the blond cyborg knew the rampaging cyborg which destroyed his hometown existed in the gulf between his own strength and the bald man's strength.

Genos wasn't strong enough to face that creature.

Not _yet._

Not at his level of skill and strength.

He needed something more. Something which would push him from the level he was at, to the level he needed to be.

Genos needed whatever **HE** had.

Whatever had pushed **HIM** to that level!

"Hold on!" Genos yelled, catching the bald warrior's attention, the man briefly turning with an inquisitive sound. "Please, tell me your name!"

"Oh," the naked man grunted, still meeting Genos' one remaining eye. "It's Saitama."

"I'd like to be your disciple," the cyborg pleaded.

"Oh sure," the man, Saitama, replied easily as... he turned to walk away, the tension of the entire encounter draining. Then he turned back, realization hitting him. "Eh?"

Saitama considered Genos, laying on the ground.

"Your name?" The bald warrior god finally asked quietly.

"Genos, Saitama-sensei!" The cyborg replied, clenched fist scraping the concrete beneath.

"Come to my apartment when you're fixed up, I guess," Saitama concluded. He scratched his chin for a moment, frowning as he thought. "It's at 221 B Road. Apartment 306. Sorry, had to remember my new place. The attack a few weeks ago forced me to relocate."

Their business concluded, at least as far as he was concerned, the bald powerhouse simply walked off, disappearing around a corner a few streets down from the one they'd been fighting on.

Genos frowned as he began the work of getting himself ambulatory again. For the most part he was a wreck: He was missing his right eye, his left arm, and two solid swipes out of his torso. His legs were damaged, but he determined that they'd be functional if he could patch the right wires back together.

The severing of his spine and main trunk wasn't a big deal: As long as he didn't force his body through the stress of combat, he'd be able to make his way back so he could be repaired properly. He'd been designed to last under fairly impressive pressures, after all.

It took him ten minutes, but careful welding using the burner on his right hand had allowed him to stand under his own power.

It was then that he noticed the young green-haired girl flying to the area surrounded by a green glow, pausing to stare between the bloody building, the split in the concrete and the clouds above, before turning her baleful gaze on the cyborg, crossing her arms and frowning.

"Hey, you! You're not strong enough to have killed whatever left you in that state like this. Not in a single strike like that. Was it a bald man who turned the monster into a bloodstain on that wall?" The young girl demanded, floating down. Whatever glowing power was allowing her to fly also kept the dress the young woman was wearing from fluttering in an indecent way, thankfully.

The cyborg didn't have anything resembling a sex drive after how thoroughly he'd been converted, but some part of him still thought that seeing some annoying little girl's panties would get him in trouble.

She looked fourteen or fifteen.

At best.

Genos was about to answer when he heard the rapid sounds of feet on concrete, and found another teenager in baggy pants, red turtleneck, and ridiculous punk hairdo sprinting down the road, a baseball bat clenched firmly in one fist as he held a black school jacket over the other.

"Tatsumaki, was it that guy again?" The punk finally panted lightly, coming to a rest nearby. He had time to frown in realization before green energy surrounded him and hurled him at ridiculous speeds towards a nearby building.

Rather than splatter against it like Saitama had splattered the mosquito monster, the teenage punk slammed his bat into the street, creating a crater and allowing him to flip mid-air and plant his feet against the building, a huge crater forming on the wall as the man crouched to bleed momentum, before allowing himself to drop to the ground with a small crash of shattered concrete.

"Hm! This one was about to answer me when you stuck your nose in, Metal Bat!" Tatsumaki huffed, floating towards the man in question, hands planted on hips as she bowed in mid air to lend her glare at the young man more weight. "Honestly, why'd you even bother coming?"

"I'm as eager to find this guy as you!" Metal Bat grunted tapping his bat into one hand, the teenager sneering at the powerful girl, the green-haired powerhouse drifting closer in retaliation.

The cyborg watching the two finally coughed.

"You are looking for Saitama-sensei, yes?" The cyborg finally asked, and though the name didn't appear to be recognizable to them.

"Saitama-" the teenage punk began.

"-Sensei?" the green-haired brat continued, staring at the cyborg.

There was an element of shock there, as well as confusion.

"I'm more than willing to allow you to follow me when I next meet with him," Genos promised them, before frowning. He gestured to his ruined body before continuing. "However, he told me not to appear before him until I corrected the damage I took in this fight. We will need to meet here tomorrow if I am to lead you to him."

The green-haired girl frowned, the same aura shrouding her as she glared at the cyborg.

"Oi, we want to go now. If you know what's good for you, you'd better lead us to him right now," she demanded, raising her hands ominously. At her back, the teenage punk had slung his bat across his shoulders, despite the grimace he wore at his compatriot's tactics. It was clear that both would be willing to fight, and kill, for Saitama-sensei's location, right at this moment.

"I may not scare you, but would you really attack me just because you don't want to wait a day?" Genos replied calmly, frowning. "Obviously if the situation turns dire and we need him I'll freely give up his location, but I do not feel the situation is dire. So you will not get his location from me. Not today."

"Hmm... And tomorrow? There are more than us two looking for him." Tatsumaki challenged.

"If he cared about how many you brought, I wouldn't admire his power," Genos replied blandly, before walking away.

oOo

The people showing up to meet Genos' new master began arriving quickly once he got to the meeting location, freshly repaired by Doctor Stench and now back to combat effectiveness.

The first two were the two from before, Metal Bat and Tatsumaki, the former walking up to the meeting point with his bat casually slung across his shoulder, the latter floating down from the sky wrapped in the same ethereal energy as before.

The next was an old man, wearing simple black slacks and a turtleneck, a shock of short white hair sticking up as he calmly walked up to the group, his back bent and stooped. Were it not for the first two, Genos would have assumed this third man, who introduced himself as "Silver Fang", was just like any of the dozens of other old men he'd passed: That he was a part of their group meant he was likely within the same threat level as them.

With the old man was a guy who looked like he came out of a samurai movie: The middle-aged man had his black hair pulled into a high ponytail, chewing on a blade of grass. He wore a black haori over loose robes, and only the red cape on his shoulders looked out of place. However, the way he caressed the pair of katanas sheathed at his side put Genos on edge.

He'd introduced himself as "Atomic Samurai".

The pair made small talk with Metal Bat while Tatsumaki feigned boredom as she waited.

The next two seemed to almost appear out of nowhere, dust kicking up as they came to a stop, freezing with their swords at one another's throats. Genos noted that the rest of the people gathered had barely batted an eye at this behavior.

"Slow. Very slow. You dropped your guard through 7th Street, Lightspeed Flash!" The first declared. If it weren't for the incredibly tight black bodysuit which left zero room for interpretation, Genos would have thought the speaker was a woman, based on how slender his build was, how delicate his features were, and the ponytailed hairstyle, despite the strange facial markings. He wore a grin as he sheathed his ninjato.

"And you were completely open when you crossed the street at the rooftops of 23rd Street, Sonic Speed of Sound," the second replied calmly, sheathing his katana. Like Sonic, the light-haired man had facial features closer to a woman's than a man's, though his build was slightly more masculine. Like his opponent, he also wore a black bodysuit, though this was offset by the white cape he wore and the armor on his upper chest.

Genos waited for another minute, before frowning at Metal Bat.

"Is this everyone, or are there others?" The cyborg finally demanded, crossing his arms and frowning at the group. "If you're all going to ruin my lesson with Sensei, I want you to do it all at once."

"This is everyone who planned to be here, Genos-kun," Silverfang finally admitted, gesturing down the road with one hand. "Please, lead us to your Sensei. Lead us to Saitama. We would like to meet him."

While the group following him displayed varying degrees of annoyance at the pace he'd set, Genos ignored it as he made his way to the address his GPS was indicating.

He knew who most of the people following him were, and they were the top-tier S-Rank Heroes of the Hero Association: They were the strongest of strongest heroes, the heroes the world relied on when the world was going to end.

One of them indicating interest in a person would be notable.

Six?

That was a person who could make or destroy the world, unless the Hero Association banded against them. With nearly half of the strongest warriors of the Hero Association at his back, Genos knocked on the door of the man who'd labeled him his disciple.

Dressed in a ridiculous yellow jumpsuit, red gloves and boots contrasting the bodysuit while an ostentatious white cloak completed the ensemble, Genos' new teacher glanced across everyone before focusing his iron-gaze on the cyborg.

"Genos, what's up? If this is a trap, it sucks," Saitama informed the cyborg, unlatching the door and stepping outside.

"These followed me from yesterday, when I nearly died," Genos responded honestly, though he held his hands up placatingly and stepped in between his new teacher and the heroes who'd accompanied him. "They want to know how you're as strong as you are. They want more heroes like you."

"I have a strict exercise regimen. If they can follow it, I'll accept them as my students," Saitama-sensei replied, before smiling once. "If they want to get as strong as me... I'll give them the same exercise regimen I received."

That was... terrifying to even imagine.

OOo

Author's Notes:

Chapter 2, dudes. Did not expect this story to explode as it has, and I'm glad you're enjoying it. Comedy next chapter, I swear.

Hope you enjoyed.

-Gaming Ikari


	3. Chapter 3

Serious Saitama

Chapter 3: Absolutely Ridiculous

oOo

"This should be far enough," I huffed, turning to look at the strange crowd following me.

I'd been surprised when a lot more people than that weird Genos kid had shown up. All of them were... not strong, but that grey area between really weak and maybe worth fighting properly. Everyone in the crowd, from the floating preteen in the obscene dress to the old guy in the turtleneck, they had an aura of power to them.

Not enough for me to get serious like those weird mole people, but enough that I might have to sort of pay attention if they all came at me at once.

Enough for me to pay them more attention that I paid to the daily sales at the H-Mart. They had potential, for the most part. Pretty much anyone but me would have called them strong, probably.

"Far enough for what?" The floating pre-teen demanded, swiveling in position so that she could glare at me. She managed to do so while both bending forward to increase the weight of her glare while her eye level never changed, hanging from the sky like a puppet.

"Far enough for me to explain my training and to impart it to anyone who's willing to take it up," I replied, solemnly. I frowned a bit, taking in my actual student's entirely metal body as I picked my nose with a pinky. "It might not help Genos because he's a robot thing, but anyone with a human body can benefit from my training advice."

"And that is?" The old guy in the turtleneck asked, leaning forward.

"Since you guys are the good guys, I don't mind telling you, I guess," I finally shrugged, before my posture stiffened as I lifted one fist in a somewhat dramatic fashion. "The only way to attain the same power I have is as simple as it is brutal. It is a set of exercises which will push you to your brink and beyond, and make you wish for the sweet release of death."

The entire gathered group waited with bated breath, even the green-haired floating pre-teen.

"One hundred push-ups. One hundred situps. One hundred crunches," I continued to explain the brutal training regimen which had given me the power to be bored of most fights. "One ten kilometre run. Every day, keeping your air conditioner off during the summer and your heater off during the winter to train your mental fortitude. Only then can you become as strong as me."

There were a lot of shocked stares.

"Every day. Even when your joints begin to click," I added, further impressing upon them the importance of the schedule.

The silence continued, until...

"Is... Is that so, Saitama-san?" the old guy in the turtleneck asked, raising an eyebrow. Behind him, I saw several of the sorta-powerful guys looking at the floating green-haired pre-teen and the way her face was going red. Obviously she was embarrassed that she wouldn't be able to keep up with the training.

It wasn't her fault. Maybe puberty would be kind to her and she'd be able to endure some hard exercise one day.

"Perhaps I'm too old to endure the training," the old guy mused, before slapping the strange kid with the pompadour forward, the teen's baggy pants nearly tripping him as he stumbled in my direction. "Metal Bat here, however, is of an ideal age to learn from you! One of the youngest S-Rank Heroes of the Association. He's raw, but he could learn a thing or two from you!"

I glanced at the guy, taking in the wariness as he looked at me in turn. Despite the old man's casual statements, he probably would have been fun to fight casually. If he was vouching for the weirdo with the pompadour, maybe he was worth training.

Turning to said weirdo showed me a kid with a strong body, just from the way he shifted. His footing was fairly grounded and there was a definite tension between his arms which lent him to very quickly swinging the bat in his hands. The punk looked like he could take a few good hits to the face too (and definitely had in the past), so he wasn't a total waste of time.

I nodded to the old guy.

"This one as well," the blond-haired speedy guy said, shoving the ninja look-a-like forward. What followed was something I'm pretty sure only I followed, if the way everyone failed to react was any indication. I think the preteen was blinking when it happened. As the blond katana knight guy effortlessly outmanouvered the dark haired ninja dude, the two changing positions about a hundred times in an instant. He finished by tripping him towards me, shrugging a bit when the ninja-haired kid turned to glare at him. "Sorry, Sonic. We've both always known I'm faster. When you're faster than him, we'll resume our rivalry."

"Lightspeed!" The ninja dude, Sonic, started to yell. As one sensei taking on a student from another, I reached out and grabbed the back of his shirt before he'd completed his first step away from me. "Huh?"

"I'm teaching you now, not him. Learn quickly and you can get out of it," I promised, frowning. "Learn quickly. I don't want to deal with you."

"Hmph!" The brat snarled, turning away. I let go of the turtleneck he wore, while also promising myself to teach the guy to wear less form-fitting clothing. I was seeing far too much of what I didn't want to see right now, and if I was going to be teaching this idiot, I wanted to see far less than I was seeing now.

Tight spandex has a place and purpose, and neither revolves around the crotch the way Sonic's spandex was bunching and crowding on certain features of his... definitely _his_... _**anatomy.**_ I shuddered to myself, mentally purging the image with the same fortitude which had allowed me to gain the strength I'd gained since the day I decided to become a hero.

"Anyone else? The pre-teen looks like she could use some exercise," I grunted.

"Preteen?" The old man in the turtleneck asked, confused, before his eyes went to the girl in question. Her face was going an impressive shade of red which kinda clashed with the color of her dress and hair. She probably should have thought of that when she was making her superhero outfit. The white-haired dude raised a hand, hesitantly, towards the girl in question. "You mean, Tatsumaki-san?"

"Yeah," I confirmed blandly, noting that the sword-guy was coughing and smiling like he was trying to hide a laugh. "She's not much now, but maybe when she hits puberty she might be something impressive. If she grows bigger she might have enough reach to be effective. Miracles can happen, you know."

The glow of green around her was just for an instant so fast it'd have given the two pretty boys pause, and then an empty apartment building was hurled at me. I slammed my three new students into the ground so it'd pass over them before turning to insure that the soon-to-be-rubble wouldn't hit anyone, and that moment of inattention cost me as the building struck me full-force, blasting into my right side and lifting my right foot from the ground.

My left foot remained planted, and the force of the building imploding against me sent a violence blast of air against everyone present, even as the rubble tumbled down the road and crashed into other empty buildings, the rumble of stone and chaos heavy in the air.

I waited for the sound to die down a bit.

"...plus, I'm pretty sure she'll probably get better control of herself once she grows up a bit more. You know how teenage girls are," I confided to the samurai dude, who'd given up on trying to hide his laughter and was now openly guffawing.

Weird.

"I'M OLDER THAN YOU!" The pre-teen, or probably not, yelled and I was suddenly surrounded with a green energy which yanked me up about ten feet to float in the air. I didn't feel anything holding me or any pressure, but it was like gravity and inertia had decided to just go home for the day. I could only watch as the green-haired weirdo floated closer. "Well!? I'm the strongest esper in history! I could throw you into the sun with a thought! Unless you apologize to me now I might do it! So what are you going to do now that you've let me catch you!? Huh!?"

I considered her angry face for a moment before lifting my right foot, high enough that my thigh was parallel with the ground. She scowled at the movement. Then...

I stomped my foot down.

Hard.

My right foot crashed into the asphalt of the road first, though I quickly brought my left foot down to match it, and only buried myself up to mid-shin in the road before I stopped my descent. I raised my right pinky finger and dug deep as I looked up at the green-haired chick.

"Older than me? Huh. Puberty was really poor to you, wasn't it?" I offered with sympathy, flicking the booger on my pinky to the side. I would have expected her to be angry, but her face had gone almost as white as my plates at home and she was staring at her hands instead of me. So I ignored her, turning to my three new students. "So, we'll meet up at my place tomorrow morning at nine. I've got to go hit up the store. They've got a great sale on udon and I'm not going to miss out on that. See you tomorrow."

I then left, nobody present moving to stop me. Or even offer me a parting word in turn, even my new students. Rude, guys. Rude. At least offer me a goodbye if I'm going to be teaching you.

Like my day hadn't been annoying enough, the udon I was planning to pick up for the sale was sold out, and instead I just bought some eggs and spinach that were on sale. If I hadn't agreed to meet with that Genos kid or any of the other strangers, I would have made it in time for the udon I wanted, instead of having to make myself spinach omelets.

Sometimes the sacrifices you have to make to be a hero are too tough, too drastic.

I got home, cooked myself my omelet, and then read two volumes of Mazinger Z+ before I decided to turn in, leaving a small bowl of food on the porch for the stray cat that drifted by every once in a while.

The lack of udon in my belly burned me. I could always take it out on my new students tomorrow.

That thought drifted in and out of my mind as I finally dozed off.

oOo

Author's Notes:

I went with first person to try to better convey Saitama's thoughts here. Sorry that it's been a while. I'm going to lie when I say I promise I haven't been playing video games and watching anime and doing nothing related to writing for a year.

#SorryNotSorry

Next season of anime looks amazing, though. Boku No Hero Academia Season 2! Woo!

-Gaming Ikari


	4. Chapter 4

Serious Saitama

Chapter 4

oOo

"Oi, baldy, where are we going?" The bat carrying punk demanded from behind, sounding slightly winded as I guided my three new students from Z City and into the wilderness. After the the school thug, cyborg, and way-too-tightly-clad ninja had shown up at nine in the morning, I'd told them I'd need to evaluate them if I was going to train them.

For calling me baldy, I promised myself I'd punch the bat kid first. Not too hard or anything, but hard enough to make him not use that nickname again.

We got to a giant canyon that looked pretty devoid of life, so I called a stop, frowning at the bat guy as he stopped to catch his breath. He was definitely going to be getting some specialized stamina training for panting for breath like that. Genos and the ninja kid looked fine, though Sonic's hair was a little matted with sweat. Maybe he'd need some stamina training too, but clearly not the way the school punk did.

"So you guys spread out. Whenever you're ready to attack me, do it all at once. I need to figure out your skill level," I offered, moving to stand in the centre of the canyon. My pinky finger explored the wax in my ear as I turned back to face them. "Take your time and come up with a plan. I don't want you coming at me one at a time. I want you to try to work together to take me out. And come at me like I'm those underground things from before. Show me your true power."

They talked for a moment, and all three nodded once as they seemed to come to a plan, before they spread out in a more or less circle around me. I couldn't call it a one hundred and twenty degree spread, but it probably would have taken a protractor or something to call it accurately.

"Attack at any time, guys," I asked, tapping one foot.

For three seconds, nobody moved. At three seconds and a tenth, that Metal Bat kid launched himself at me pretty hard, his bat over his shoulder for a swing which would connect when he got to me at four seconds. At three seconds and six tenths, Genos threw his arms back and used the blasters on his arms to burst himself forward, and he'd be arriving in about four tenths of a second.

At three seconds and nine tenths, Sonic darted at me and would be completing his slash when he got to me.

They'd come up with a three-pronged pincer attack. It was kinda impressive, if you couldn't process things at the speed I did in combat. They probably could have killed as many of the underground warriors as I did with teamwork like that.

Of course, I couldn't let them complete it.

I shifted slightly to the side and very lightly punched Metal Bat's arm up about an inch, which made his bat intercept Genos' downward swing as I stepped back and out of the way. With ninja boy closing in on my back, I stepped on the bat and the arm to further distract them as I pushed myself skyward, avoiding the ninja-to slice by Sonic which would have decapitated me if I was slow and weak enough.

I'll give Sonic this: While Metal Bat and Genos were still recovering from the failed assault, he used them both as a launch pad to suddenly change the direction of his momentum to follow me into the air. He almost got me a couple times in the hundreds of swings he directed my way in the next second or two, before I booted him back into the pile of my other two students, who'd just recovered.

The impact sent all three sprawling across the canyon floor, though before I'd even landed the cyborg was pressing heat into the ground and somehow making lightning which rippled back up his arms and made him float. Weird. Then the blond dude was suddenly as fast as Sonic just as my feet touched the ground, ripping the earth apart as he took a random direction charge at me, launching a lightning-laced kick that was so easy to dodge I bent forward.

Ninja dude was pretty damn opportunistic by being ready to decapitate me like that. I grabbed the lead hand on his double-handed swing and used that to take a step forward and hip throw him into the school punk guy, bowling them both over and over and way out of range of me as the pair tumbled across the canyon floor.

"BURN!"was the only warning I got as I turned to face Genos, who had what looked like hundreds of guns coming out of his robot arms as he stared me down. I had a quarter second to act, so I punched the ground and spread my fingers as I pulled it out, flinging huge chunks of rock into the air, before fire was everywhere.

So I jumped and rebounded off one of the suddenly-molten rocks I'd flung into the air, landing lightly behind Genos even as he exhaled after his attack. I shifted my foot to let him hear me enough to turn towards me and brace for what was coming before I booted him halfway across the canyon with a standing stomp into his ribs, which was apparently what Sonic was waiting for.

The speedy ninja dude tried to take my leg off at the knee almost as soon as I made contact with Genos' ribcage. As soon as I saw it coming I rotated my body while shifting my leg to keep it on course, and did a backflip towards my target which also shattered Sonic's ninja-to with my free foot. I hadn't even landed when Metal Bat was completing his jumping overhand attack, a double-handed swing aimed directly at my skull.

It kinda stung as I blocked the bat with my right forearm, which drove me hard into the canyon floor and threw up a bunch of chunks of rubble right when the first batch from before was just hitting the ground. I smiled at the shocked look on his face at me blocking the strike as easily as I had before I uppercut him hard enough that he'd probably hit one of the canyon walls. Yet despite that... His death-grip on his weapon never wavered.

He'd probably taken a lot of face hits before to keep his hand on his weapon. Or at least that's what I assume based on his looks. For a teenager he was remarkably ugly and beat up. Like he took a lot of shots to the face.

Ninja boy was after me again, and he wasn't slow. He was fast enough I kinda had to pay attention, but with his weapon shattered and only his tools available, it was just a case of catching and discarding his shuriken. When he started to retrieve them to use them once again, once I caught them I started to fling them out of orbit so they'd never trouble anyone, or me, again. After he'd started to slow down, I closed in and kneed him in the gut and sent Sonic tumbling across the canyon.

" **BURN!"** I'd heard that before, but this time some sort of core-thing in Genos had been pulled out he'd shoved it into his arm. The amount of fire was about the same, but the temperature of it was a LOT higher. I debated dodging the fire before simply deciding to deal with it the way I dealt with most of my problems these days.

I punched the fire, and the bow wave and sheer pressure of my strike dissipated the blast entirely. Seeing as Genos was still recovering from the blow based on the steam he was breathing as he listed to one side, I spin-kicked him into the canyon wall a little more lightly than I might have, normally. He still struck and stuck there for a moment, cracks spreading from his point of impact.

I didn't have much time to admire my handiwork, because Metal Bat was closing back on me. Damn he was slow and obvious: I'd have to work on that part going forward, because his blows had enough power that I might have had to pay attention to him if he were a little more subtle. Rather than tank the blow the way I had before, I slid down and under his swing before I kneed the bottom of the bat, sending it out of his reach before punching him in the face.

Like I said, I can't do much worse to his face than has already been done. Maybe surgery will fix his nose this time. God knows it hadn't the last.

Sonic caught the tumbling bat I'd knocked free from Metal Bat, and he closed on me with it with confidence even though I could see the way his swings wavered that he was unused to using the weapon beside his blade. Still he whipped the thing through the air around me with considerable skill as I bobbed and weaved, the club almost rolling over me at times as Sonic came close to hitting me. Thirty-four strikes in and the ninja had left me enough openings that I felt okay booting him across the canyon floor once again, separating him from Metal Bat's weapon in the process.

"Machine-Gun Blow!" Ah, there was Genos. I turned, and though I wasn't pressed to the limit of my speed by him, the cyborg was still pretty damned fast and powerful with his blows: I allowed him to push me across half the canyon, testing his stamina, before I realized that he'd keep going until he ran out of steam at this rate. He'd also put his core-thing back in his body, because it wasn't acting like a giant bicep anymore.

Between one punch and the next, I kneed him hard in the gut and aimed him towards Sonic, who'd barely recovered from our last round of exchanges. Both of the heroes went down and I paused as the earth shook, turning towards the source.

Damn, that Metal Bat kid looked pissed. He'd recovered his bat while I was playing with my other two students, and he looked half beat to shit. Still, the grin on his face with the blood dripping down his jaw might have been frightening if he was a threat to me.

"My true strength, Saitama-sensei!?" The pompodour punk demanded, wiping the blood from his face. I felt the increase in his strength as he momentarily screamed, his injuries from the fight seeming to disappear for a moment. "Fine! Here it is! Enjoy my Savage Tornado!"

With those words, Metal Bat began to spin like a top out of hell as a whirlwind encompassed both of us. I could have jumped free of the attack easily, but where would the fun be in that? Instead, I weathered the attack, deflecting each shot with precision even as the young man making the attack utterly exhausted himself in the all-out technique, finally slowing as he ran out of energy.

"Not bad," I commented, before booting him into the canyon wall. He stayed there when he got stuck in it.

Sonic and Genos struck both at once then, but I was getting hungry. I grabbed them both by the throat and smashed them into the same wall I planted Metal Bat, lashing out with a kick to shatter the wall of the canyon into a million pieces as I dropped the duo, catching my one immobilized student in the form of Metal Bat as I did so.

"Not bad, but I can clearly teach you all something," I stated, ignoring the looks on their faces as the sounds of thousands of tonnes of shattered canyon hit the wasteland in front of me. I jiggled Metal Bat a bit where he lay on my shoulder, earning a sputtered half-consciousness from him in the process. "Let's go get some udon. My treat. You guys did better than I expected."

I didn't bother to wait as I started to sprint back to Z-City. If we were in time, I could get them all to the half-price stand before the prices went back up. They'd done well enough I was willing to treat them to half-price udon, at least.

oOo

Author's Notes:

So yeah... The House of Evolution arc got cut. Aside from MAYBE Asura Kabuto, I don't see anyone from that place surviving the 'dream' sequence any more than the rest of the huge percentage of humanity which got cut down, so including it was never really on the cards.

Instead, you got Genos, Metal Bat, and Sonic versus Saitama, in a battle which takes the awesomeness of the original Genos vs Saitama spar to new heights.

Because sometimes I have to remind people I write god-damned awesome fight scenes.


End file.
